Sludge scraping apparatus

ABSTRACT

A work member comprising a sludge scraping member is guided by a monorail guide so that the guide and work member can be constructed in the most simplified form, and the working performance can be made excellent at the same time. By simplification of the construction, the installation work can be made easily, and the running and maintenance costs become low.

FIELD OF THE INVENTION

The present invention relates to a sludge scraping apparatus fortreating by scraping sludge or sand sedimenting in a treatment pool suchas first or last sedimentation pool in one direction of the pool.

BACKGROUND ART

For example, in the first or last sedimentation pool of sewage atreatment plant, it is designed to sediment sludge in the bottom of thepool, and scrape it in one direction of the pool, and discharge thesludge out of the pool. The design is the same in a tap water treatingplant.

As one method of sludge scraping, the flight circulation chain drivingsystem is known.

This system comprises a plurality of rotary shafts rotatably mountedwith the axial center directed in the width direction of the pool,sprockets mounted on each rotary shaft by two pieces each set apart, andright and left chains applied through these sprockets. At the outer sideof the chains, a plurality of flights (scraping plates) are provided atspecific intervals in the circulation direction, and as these flightsmove along on the guide rails provided in the bottom of the pool, theflights scrape and collect the sludge in the bottom of the pool in onedirection, and bring the sludge to the sludge pit. The sludge is pumpedout of the pit and discharged out of the pool.

This chain driving system is large and complicated in structure,expensive, and difficult to install, and it is high in maintenance costbecause of circulatory motion, and is inferior in economy.

On the other hand, instead of the chain circulation system, the systemof moving along the bottom of the pool linearly and reciprocatively isknown. The system comprises a longitudinal guide (guide rail) providedin the bottom of the pool, a work member for moving along the guide,drive means (rope or the like) for moving the work memberreciprocatively, and a scraping member attached to the work member, andit is designed to scrape and collect the sludge settling in the bottomof the treatment pool in one direction by the motion of the scrapingmember, and discharge out of the pool.

It has the following defects.

In addition to guides and their mounting devices, two guides, right andleft, are provided apart from each other in the width direction of thepool, which require a large work member straddling widely between theguides. Accordingly, the structure was very large and complicated, andit was expensive and difficult in installation, and still more themaintenance control cost was high for keeping circular motions and itwas not economical.

It is hence a primary object of the invention to present an apparatuswhich is simple in the entire structure and easy to install, andinexpensive on the whole.

SUMMARY OF THE INVENTION

The invention presents a sludge scraping apparatus comprising a guidehaving a longitudinal direction in a sludge scraping direction of atreatment pool, a work member moving along the guide, drive means formoving the work member, and a scraping member attached to the workmember, thereby scraping and collecting the sludge deposited in thebottom of the treatment pool at least in one direction by the motion ofthe scraping member, and discharging out of the pool, wherein the guideis a monorail, and the work member is designed to move reciprocativelyalong the guide.

Further scope of applicability of the present invention will becomeapparent from the detailed description given hereinafter. However, itshould be understood that the detailed description and specificexamples, while indicating preferred embodiments of the invention, aregiven by way of illustration only, since various changes andmodifications within the spirit and scope of the invention will becomeapparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description given hereinbelow and the accompanying drawingswhich are given by way of illustration only, and thus are not limitativeof the present invention, and wherein

FIG. 1 is a side view showing an embodiment of the invention;

FIG. 2 is a plan view of the embodiment of FIG. 1;

FIG. 3 is a side view showing an embodiment of a double-scraping typesludge scraping apparatus;

FIG. 4 is a sectional view taken along the line K--K in FIG. 3;

FIG. 5 is a sectional view taken along the line L--L in FIG. 3;

FIG. 6 is a sectional view taken along the line M--M in FIG. 3;

FIG. 7 is a sectional view taken along the line N--N in FIG. 3;

FIG. 8 is a side view schematically showing a second driving method of asludge scraping apparatus of a two-blade type;

FIG. 9 is a side view schematically showing a third driving method;

FIG. 10 is a side view showing a fourth example of driving method;

FIG. 11 is a perspective view showing a drum with a built-in motor;

FIG. 12 is a side view schematically showing the drum in FIG. 11;

FIG. 13 is a side view showing an embodiment of disposing a drive sourceso as to be movable above the sludge scraping apparatus;

FIG. 14 is a side view showing an embodiment employing a screw shafttype driving method;

FIG. 15 is a longitudinal sectional view showing an embodiment fordischarging the sludge from the scraping member through the bottom ofthe pool by a screw system;

FIG. 16 is a perspective view showing an embodiment in which the bottomof the pool itself serves as a guide;

FIG. 17 is a plan view showing an embodiment of a sludge scrapingapparatus of underground installation type;

FIG. 18 is a side view of the sludge scraping apparatus of FIG. 17;

FIG. 19 is a fragmentary perspective view of the sludge scrapingapparatus of FIG. 17;

FIG. 20 is a general cross-sectional view showing another embodiment ofthe present invention;

FIG. 21 is a plan view of the sludge scraping apparatus of FIG. 20;

FIG. 22 is a sectional view taken along the line F--F in FIG. 21 on theleft part, and along the line E--E in FIG. 21 on the right part;

FIG. 23 is an enlarged sectional view of essential parts of theapparatus;

FIG. 24 is a plan view of the device shown in FIG. 23;

FIG. 25 is sectional view taken along the line S--S in FIG. 24;

FIG. 26 is an enlarged side view of essential parts of the work arm,work roller, and return roller;

FIG. 27 is a plan view of the work arm, work roller, and return roller;

FIG. 28 is a longitudinal sectional view of a drive source;

FIG. 29 is a cross-sectional view of the drive source of FIG. 28; and

FIG. 30 is a schematic view showing a further different embodiment.

PREFERRED EMBODIMENTS OF THE PRESENT INVENTION

To facilitate a better understanding of the present invention, thepresent invention will be described with reference to the accompanyingdrawings.

FIG. 1 and FIG. 2 show one embodiment of the invention. The settlingpool of this embodiment is a first or final settling pool in sewagetreatment plant, and rectangular in a plan view extended in onedirection (the lateral direction in the diagram). The settling poolcomprises right and left side walls, end walls which form respective endportions in the longitudinal direction, and a bottom wall sloping downmoderately to the left side in the diagram. Sludge spontaneouslysediments on the bottom of the pool. In this embodiment, numeral 200denotes a single track type (monorail type) first guide, which is asquare tube, and holes 201 for operation when fixing are provided atproper side positions of the guide 200, and a longitudinal second guide202 with a slightly smaller square tube than the guide 200 is fixedthereon. The second guide 202 is also of monorail type. At one end ofthe first guide 200, a post 203 is disposed, and it is erected and fixedso that the upper end may reach over the pool.

Numeral 204 is a work member, which is a carrier moving in reciprocatingmanner in the lateral direction in the diagram, and the work member 204is a frame body, consisting of a main member with a rectangular planeframework, and pedestals extending downward from four positions of themain member. In the front part of a pit 205 side of the work member 204and its rear part, upper rollers 206, 206 rolling over the second guidemember 202 are provided, and side rollers 207 rolling over the sidesurface of the first guide 200 are disposed at the pedestals so as tocontact with all four points.

Numeral 208 is a rotary shaft disposed as a lateral shaft in theintermediate portion between front and rear ends of the work member 204,and an oscillating arm 209 capable of oscillating back and forth isdisposed on the rotary shaft 208 at a position corresponding to theinside of the work member 204. A pair of right and left lower arms 210are provided on the rotary shaft 208 at positions corresponding to theoutside of the work member 204.

The lower arms 210 are furnished with a band-shaped scraping member 212.The scraping member 212 is designed to oscillate always reversely whenthe oscillating arm 209 oscillates back and forth. The scraping member212 can select both the backward slant position indicated by the solidline in FIG. 1 and the vertical position indicated by virtual line.Numeral 213 is a stopper in vertical position.

At the upper end of the post 203, a pair of right and left drive drums(a part of driving means) 215, 216 are provided. The drums 215, 216 canbe independently rotated by drive sources (a part of driving means) 217,218. A first wire (wire rod, a part of driving means) 220 indicated bysolid line which is wound on one drum 215 passes through the first guide200 along the broken line through a first wheel 222 provided at the backside of the rear part of the post 203, and moves through a second wheel223 provided at the end portion of the guide 200.

The first wire 220 is connected to the oscillating arm 209 through athird wheel 224 in the rear part of the work member 204 from the secondwheel 223. On the other hand, a second wire (wire rod, a part of drivingmeans) 226 indicated by single dot chain line is wound on the other drum216, and is connected to the oscillating arm 209 through a fifth wheel228 and a sixth wheel 229 on the work member 204 from a fourth wheel 227provided at the front side of the post 203.

Numeral 230 is a balancer provided at the front end of the oscillatingarm 209, and is used for securely changing over to the backward slantposition of the scraping member 212. Numerals 231, 232 are right andleft independent action type brakes provided at the front and rear sideof the post 203, and 233 is a spring provided in the wires 220, 226.

This scraping apparatus repeats the cycle of scraping in the leftdirection in the diagram and returning to the right direction. That is,in scraping motion, the drum 215 is driven while the brake 231 isreleased, and therefore the first wire 220 is pulled. At this time, thebrake 232 is in locked state, and the springs 233, 233 are stretched, sothat the motion of the work member 204 by the second wire 226 is locked.Consequently, the oscillating arm 209 oscillates in the right directionin FIG. 1, so that the scraping member 212 is held in the verticalposition. Accordingly, the work member 204 will not be driven before theoscillation of the scraping member 212 to the vertical position.

Upon reaching this state, the locked brake 232 is released, and the drum215 is driven, and the work member 204 is driven in the left directionin the diagram, thereby exerting scraping motion. The work member 204operates stably by the upper roller 206 and side roller 207. Thisoperation is realized by the winding direction rotation of the drum 215and the loosening direction rotary motion of the drum 216.

When the scraping member 212 reaches up to the pit 205, the scraped andcollected sludge is dropped into the pit 205. Afterwards, the brake 231is locked and the brake 232 is released, and the drum 216 is rotated inthe winding direction. As a result, the spring 233 is stretched, and thesecond wire 226 indicated by single dot chain line is pulled, and theoscillating arm 209 oscillates in the left direction in the diagram, sothat the scraping member 212 is changed from the vertical position tothe backward slant position. Therefore, the settling sludge will not bescraped back by the scraping member 212.

At this time, the first wire 220 is locked. And when the brake 231 isreleased and the drum 216 begins to wind up, the second wire 226 ispulled so that the work member 204 is driven in the left direction andreturned. At this time, the drum 215 is simultaneously rotated in theloosening direction.

FIG. 3 through FIG. 7 relate to another embodiment of the invention,showing a sludge scraping apparatus of double-scraping type comprisingfront and rear scraping members 523, 523. In this embodiment, as shownin FIG. 4, using two I-section channel members, they are disposedparallel right and left and joined with a junction panel 500, therebyfabricating one monorail type guide 501. This guide 501 is fixed alongthe middle of the pool bottom wall 504 by an anchor 503 through aholding plate 502 in the lower part.

The guide 501 is extended in the longitudinal direction of the pool asshown in FIG. 1, and wheels are provided at both ends of thelongitudinal direction. Although the post 220 is not disposed at one end(FIG. 1), the driving method is approximately the same as in FIG. 1.

Numeral 505 is a work member, and is formed in a frame body by a pair ofright and left main body frames and a transverse member crossing them.Numeral 506 is a lipped upper roller, and is disposed at six points atslightly lower positions of the work member 505. The upper roller 506rolls over the guide 501.

Numeral 508 in FIG. 4 is a side roller, and is disposed through a rollerbracket 510 installed on four front and rear pedestals 509 so as toprevent lateral sway by hitting against the side surface of the guide501. Numeral 511 is a hold-down roller, and is attached to the pedestals509 so as to hit against the lower surface of the upper lip of the guide501. At the front and rear sides of the side roller 508, roller covers512 are provided as shown in FIG. 7.

Numeral 514 in FIG. 3 denotes bearings, four of them 514 are provided atrespective four front and rear points of the work member 505, and otherbearings 514 in FIG. 3 are fixed on a front stopper 515 disposed so asto extend right and left from the pedestals 509. Rotary shafts 517 arerotatably supported by these bearings 514 above the work member 505. Tworotary shafts 517 are provided parallel at front and rear sides, andthree sets of right and left arms 518 are provided on each shaft 517, soas to oscillate back and forth together with interlock arms 519, 519projecting in the middle of the rotary shafts 517. The front and rearinterlock arms 519 are coupled with an interlock link 520.

The front and rear arms 518 are constituted as to be in verticalposition by hitting against the front stopper 515, and set in rearoblique retracted position as the front arm 518 hits against a rearstopper 521 passing through the lower side of the work member 505 andextending right and left therefrom. Numeral 523 is a scraping member forsludge, being a rubber plate, and the scraping member 523 is attached tothe lower end of the arm 518, and a roller 524 provided at the rear sidethereof is guided by mounting on a rail 525 as shown in FIG. 4.

Numeral 527 in FIG. 3 is a base, and this base 527 is fixed in themiddle of the upper side of the work member 505, and two front and rearwheels 528 for guide are provided thereon. Numeral 530 is a first wire,and 531 is a second wire. The first wire 530 is linked to the front sideinterlock arm 519 through a wheel at the front end of the guide 501 byway of the internal space of the guide 501 from the drive source, andthrough the front side wheel 528 from above the guide 501. The secondwire 531 is coupled to the rear side interlock arm 519 through the rearside wheel 528 by way of a wheel 227 at the rear end of the guide 501from the drive source.

When the first wire 530 and second wire 531 act in the direction of thesolid line arrow in FIG. 3, the front and rear interlock arms 519oscillate backward. As a result, the scraper 523 is set in verticalscraping position. In this position, it is designed to scrape in the pitdirection. Having arrived at the pit position, as shown in the virtualline in FIG. 3, the second wire 531 is set in pulling state, and thefirst wire 530 is in loose state. Accordingly, the interlock arm 519tilts forward and scraper 523 is set oblique backward, thereby becomingin return position. Incidentally, as shown in FIG. 6, a reinforcingframe 532 is stretched between the front stoppers 515, 515. It may beomitted if the strength of the stoppers 515 is sufficient.

FIG. 8 shows other embodiment for interlocking the scraping member in asludge scraping apparatus of double-scraping type. Numeral 550 is aguide, which is fixed in the middle of the bottom of the pool. On theguide 550, a work member 552 is movable in reciprocating manner by aroller 551 (together with side roller not shown). Rotary shafts 553 areprovided at front and rear portions of the work member 552, andinterlock levers 554 and oscillating levers 555 are attached to theshafts 553. In an intermediate position between the front and rearinterlock levers 554, an intermediate lever 556 supported on the workmember 552 is provided, and a link 557 between the interlock levers 554is coupled to the upper end of the lever 556, while a first wire 558 anda second wire 559 are coupled to the lower end of the lever 556.

When the first wire 558 is pulled as indicated by solid line arrow, thelink 557 moves in the direction of the solid line arrow, and theinterlock lever 554 oscillates backward, and a scraping member 560 isset in scraping position. As a result, the sludge is scraped andcollected in the scraping direction shown by the solid line arrowdescribed near the scraping member 560. On the other hand, when thesecond wire 559 is pulled at the pit side, the interlock lever 554oscillates in the direction of the broken line arrow, and the scrapingmember 560 moves up in the broken line direction, then, the work member552 is moved in the return direction shown by the broken line arrow.

Numeral 561 denotes a guide roller. The scraping member 560 may be asingle-scraping type, too. In this case, one interlock lever 554 isomitted.

In FIG. 9, a rotary shaft 583 is provided on a work member 582 movablealong a guide 580 by a roller 581, and a work lever 584 and an L-shapedreceiving lever 585 are rotatably disposed on the shaft 583. In the worklever 584, a wire 586 is passing, and the work lever 584 isreciprocatively oscillated by stoppers 587 provided in the wire 586. Thewire 586 is guided by a guide roller 588, while a mounting plate 590mounting a scraping member 589 is disposed on the receiving lever 585 ina manner free to rotate in one direction only.

When the wire 586 is pulled in the direction of solid line arrow, therear stopper 587 is actuated, and the work lever 584 rotates forward,and the scraping member 589 is set in vertical scraping position by thereceiving lever 585. On the other hand, when the wire 586 is pulled inthe direction of broken line arrow at the pit side, the work lever 584is rotated in the reverse direction by the front stopper 587, and thereceiving lever 585 is lifted, so that the scraping member 589 is alsolifted. The scraping member 589 ascends or descends always in thevertical position. In this mechanism, if the apparatus returns to reachthe limit at the pool end wall, the unscraped portion left at the rearend of the pool is small.

FIG. 10 to FIG. 12 relate to a different embodiment. Numeral 100 is aguide, 101 is a work member, 102 is a scraping member, 103 is a lever,and 104 is an interlock link. Numeral 105 is a wheel, 106 is a wire, and107 is a drive device. The drive device 107 incorporates a motor asshown in FIG. 11 and FIG. 12. That is, the device 107 comprises a fixedwheel 108 and a drum 109, and a groove is formed in the drum 109. In theinside, a motor 110 with reduction gear is installed at the fixed wheel108 side, and it is constituted so that the drum 109 may be rotated anddriven as a pinion 111 fixed to the front end of the motor shaft drivesan internal gear 112 formed on the drum 109.

A pair of these motor-built-in type drive devices 107 are disposed abovethe pool, and the wires 106 are wound thereon. When one drive device 107is driven and the other one is free or rotates reversely, the wire 106is pulled as indicated by the solid line arrow in FIG. 10, and thescraping member 102 comes in scraping position, while the other scrapingmember 102 is also set in scraping position through the interlock link104. As a result, the work body 101 is driven in the pit direction, andscraping is carried out. When the other drive device 107 is driven, thework member 101 is returned in the direction of broken line arrow. Atthis time, the scraping member 102 escapes obliquely.

The individual drive system as in FIG. 10 may be also employed in FIG. 1through FIG. 9.

FIG. 13 shows a further different embodiment of the invention. That is,a guide 140 of monorail type is extended in a longitudinal direction inthe bottom of the pool. A work member 141 is U-shaped so as to straddleover the guide 140, and is driven reciprocatively. The work member 141is provided with a roller 142 and scraping members 143 disposed at rightand left sides.

On the work member 141, a hollow column 144 is set up so as to seal thewater by extending above the water level. The driving means compriseswheels 145, 145 disposed in the work member 141, other wheel 146disposed in the upper part of the column 144, a drive source 147disposed in the upper part of the column 144, and an interlock member148 such as wire or chain with one end fixed near the front end of theguide 140, being guided to above the pool through the vicinity of theother end of the guide 140 passing above the guide 140 to the wheel 145in the work member 141, then through inside the column 144 up to theupper wheel 146, and down through the column 144 to the wheel 145 in thework member 141. And by allowing extension of the interlock member 148,it is constituted so as to lift the work member 141 furnished with thecolumn 144 above the pool. Numeral 149 is a drum rotated in order toloosen the interlock member 148.

In usual driving, when the drive source 147 is rotated in normaldirection, the work member 141 is driven in the direction of a pit 150by the interlock member 148. The sediment is collected by two front andrear scraping members 143. When the drive source 147 is rotatedreversely, the work member 141 moves in the return direction by theinterlock member 148. Usually this operation is repeated.

FIG. 14 shows another different embodiment of a sludge scrapingapparatus. Numeral 10 is a settling pool, and this settling pool 10 hasthe bottom sloped laterally, and a protruding guide 11 is formedintegrally (or separately) in the middle of the bottom. A U-shaped workmember 12 straddles over the guide 11. The work member 12 comprisesrollers 13, and is free to reciprocate back and forth.

At both sides of the work member 12, the scraping members 14, 14 aredisposed so as to set in vertical position when moving in the scrapingdirection or one direction, and to escape obliquely when moving in thereturn direction. Inside the upper part of the work member 12, a screwbody 15 is fixed, and a screw shaft 16 on the guide 11 is engagedtherewith. Above the pool, a drive source is provided, and it isdesigned to rotate the screw shaft 16 through a transmission shaft (withcover) 17 and a gear box 18.

When the screw shaft 17 is rotated normally or reversely, the workmember 12 is moved reciprocatively back and forth by the screw body 15.As a result, the scraping member 14 scrapes in one direction, andreturns in the reverse direction. A cover shown by a double dotted linemay be provided, incidentally, above the moving region.

FIG. 15 relates to a different embodiment. In this embodiment numeral 50is a guide, and a machine body (work member) 52 with relatively largewheels 51 reciprocates back and forth along the guide 50. The machinebody 52 is provided with a scraping member 53 so as to scrape andcollect the sediment on a slope bottom wall 54. When the sediment isgathered to the middle in the width direction, it is dropped into aconveying route 55 formed at the lower side of the guide 50, and isfurther sent into a pit by a screw (conveying means) 56 provided in theconveying route 55. Of course, the sludge is also collected by thescraping member 53. The scraping member 53 may be composed of an obliqueblade as seen from the plane so that both ends may advance while themiddle base part may follow.

In FIG. 15, as conveying means, an evacuating method or chain scrapingmethod may be employed.

FIG. 16 shows a different embodiment of a sludge scraping apparatus. Inthis embodiment, numeral 1 is a settling pool, and a one-body guide 2 ofmonorail type is extended in the bottom of the settling pool 1. Thisguide 2 is approximately shaped in a V form.

The guide 2 is provided with a V-shaped work member 3 so as to be guidedby rollers 4 disposed on the surface of the guide 2.

This work member 3 is a heavy object, and stopping hooks 5 are providedat front and rear walls thereof, and a wire 6 is hooked thereon asdriving means so as to pull and move reciprocatively. This pullingaction is driven by a sprocket and a motor from above the pool.

The front side of the work member 3 itself forms a scraping surface 3a.When the work member 3 moves in one direction, the sediment is collectedin the direction of a pit (not shown), and the sediment is dischargedout of the system by a pump. The driving means comprises, aside from thewire, chain, screw shaft or others.

FIG. 17 to FIG. 19 show an outline of this system. Herein, numeral 301is a sand sedimentation pool, 302 is a first settling pool, 303 is anaeration tank, 304 is a final settling pool, and 305 is a chlorine feedtank.

These treating facilities are all formed within the internal space oftubular blocks 310. In FIG. 17, numeral 311 indicates a route coming upfrom a river, and it is divided into two routes 313, 313 having gatemeans 312 so as to be led into twin sewage treatment system S. Theportion projecting downward in FIG. 18 corresponds to the pit portion inthe settling pool.

The first settling pool 302 shown in FIG. 19 is combined of for blocks310, and the front and rear ones have closing parts 314 for forming aninternal space. Hence, the four blocks 310 form one partitioned space.

Numeral 315 is a flow inlet formed in the closing part 314, so thatsewage may flow in from the sand sedimentation pool 301. A similar flowoutlet is provided at the other end of the first settling pool 302, soas to communicate with the aeration tank 303. Inside the first settlingpool 302, a scraping device 320 is composed in the bottom.

The scraping device 320 has a guide 321 in its bottom. On the guide 321,a work member 322 is disposed in a straddling manner, being movablereciprocatively through rollers 323, and a scraping member 324 isprovided so as to extend to the right and left sides through the supportmember disposed on the work member 322. The scraping member 324 is tocollect the sediment flowing in from the flow inlet 315 to the pit 325side, and is guided in the manner of the monorail type.

The means for reciprocating the scraping member 324 is composed of asprocket 326, a chain 327, and a submerged pump 328 provided at thefront and rear ends of the guide 321. That is, as the chain 327 isdriven in reciprocating manner, the scraping member 324 reciprocates.

The single track type (or monorail type) herein includes both thedefinite single track and the type similar to the single track type.That is, same as in the following embodiment, the single track type iseither composed of one rail or a plurality of rails. In the case of aplurality, each rail may be adjacent parallel, close to each otherparallel, or at a short distance. All of them are defined to be ofsingle track type. Two rails set apart widely as in the prior art areexcluded.

FIG. 20 to FIG. 29 show another embodiment of the invention.

In the sludge scraping apparatus shown in the embodiment, numeral 800 isa settling pool, and is rectangular as shown in FIG. 21. Numeral 801 inFIG. 20 is a straightening plate provided at the flow-in side, andpossesses multiple holes. Numeral 802 is the bottom of the pool, and ismoderately sloped to the direction of a pit 803. Numeral 804 is a waterlevel.

X denotes the sludge scraping direction, and Y shows the returndirection. Numeral 805 is a guide, which is fixed along the middleportion in the width direction of the bottom 802 of the pool, its crosssection is in a form of a rectangular tube, and projects upward from thebottom 802 of the pool as single track type. This guide 805 is disposedone for each pool, and one end is disposed at the anti-pit side end andthe other end on the pit 803.

At one end of the anti-pit side of the guide 805, a wheel 808 forinverting and a guide hole 809 are provided through a bracket 807, andat the end of the pit 803 side, first and second lead wheels 811, 812are disposed parallel and rotatably independently as large and smallwheels, respectively, through brackets 810.

Numeral 815 is a work member, and this work member 815 is U-shaped andis disposed so as to sit on the guide 805 with the groove downward. Atfront and rear ends of the work member 815, flanged travel rollers 816are supported and disposed on a rotary shaft 817 so as to be four pointsas seen from above.

At the lateral side of the work member 815, brackets 819 are disposed atfour points as seen from above, and each bracket 819 is provided with apair of upper and lower side rollers 820 so as to contact with thelateral side of the guide 805. Numeral 821 is a first wheel providedindependently rotatably about the front side rotary shaft 817, and 822is a second wheel disposed on the upper end of a bracket 823 set up fromthe rear end upper surface of the work member 815.

From the top of the work member 815, a swing arm 825 reciprocativelyoscillatable on the vertical plane is set up, and a free wheel 826 isattached to the upper end of the arm 825. One end of the wire 827 whichis an interlock member is coupled to an L-shaped bracket 828, in anadjustable length, projecting toward the front side of the arm 825through the free wheel 826 of the swing arm 825 as a wire part of thescraping side.

The wire 827 is extended through the second wheel 822 and first wheel821, and is freely driven by a drive source 832 through the first leadwheel 811. On the other hand, in the other L-shaped bracket 829,similarly, the other end of the wire 827 is coupled in an adjustablelength. The wire 827 is extended backward through a third wheel 830 anda fourth wheel 831 provided in the work member 815, and through theguide wheel 809 and inverting wheel 808, it further extends forwardthrough the internal space of the guide 805, being thus lead into thedirection of the drive source 832 through the second lead wheel 812.

The drive source 832 is, as specifically shown in FIG. 28 and FIG. 29,constituted so as to mount a motor 834 with reduction gear on a frame833 fixed above the upper surface of the pool, and an upper sheave 836is provided on its output shaft 835, and a lower sheave 837 beneath it.The wire 827 is wound from either one of the lead wheels 811, 812, andis wound several times between the lower sheave 837 and upper sheave836, and is extended downward through the lead wheels 811, 812.

The lower sheave 837 is movable vertically in order to absorb relaxationof the wire 827 when changing over between the scraping state and thereturning state, and in order to absorb smoothly and securely, a weight838 is added to the shaft of the sheave 837, and is thrust alwaysdownward. This thrusting may be effected by other means such as cylinderand accumulator.

At the right and left side of the work member 815 in FIG. 23, a scrapingarm 840 supported oscillatably vertically, coaxially with the rotaryshaft 817 is extended backward. The rear end of the arm 840 is extendedvertically downward, and a pair of right and left scraping members 841,841 are provided through this portion. Behind the scraping member 841, alower roller 842 is provided, and the roller 842 is free to roll on apair of right and left guide rails 843 fixed on the bottom of the pool802.

The following mechanism is employed for changing over the scraping statewith the scraping arm 840 and scraping member 841 lowered, and theelevated return state.

That is, numeral 845 is a work arm, and a base part thereof is attachedto the rear right and left ends of the rear rotary shaft 817, and isfree to oscillate together with the swing arm 825. The arm 845 is anoval plate, and a work roller 846 is attached to its front end. The workroller 846 always contacts with the lower surface of the scraping arm840, and lifts the scraping arm 840 when the swing arm 825 tilts forwardfrom the vertical state. When the swing arm 825 returns to the verticalposition, it descends while always contacting with the scraping arm 840,and in order to secure the lowering action of the U-shaped scraping arm840, a return roller 847 with a horizontal axis is provided at the frontportion of the scraping arm 840 and protrudes into a groove of U-shapedscraping arm 840 to push down the arm 840 by force. It may be alsoconstituted so as to move up and down the arm 840 by the return roller847 only by fitting the return roller 847 into the scraping arm 840.

Numeral 848 is a reinforcing stay provided in the scraping arm 840.

The state indicated by solid line in FIG. 20 and FIG. 23 is the scrapingstate, and the state indicated by virtual line is the return state.Scraping is effected as the apparatus runs from the left end to theright end in FIG. 20. That is, at the left end, the scraping member 841is elevated at the return end, and as indicated by virtual line, as thewire 827 is pulled to the right direction, the swing arm 825 is raisedfrom the tilted state through the first wheel 821 and second wheel 822.As a result, the slant wall 806 connecting between the bottom 802 of thepool and the vertical wall is scraped off of the sludge sedimenting bythe scraping member 841.

When the scraping member 841 is lowered fully to the bottom 802 of thepool, the sludge deposited in the bottom of the pool is collected. Thatis, the lower roller 842 contacting the guide rail 843 advances whilerolling. The work member 815 runs at low speed stably as being guidedalong the guide 805 by the traveling roller 816 and side roller 820, andwhen the wire 827 is pulled to the right at this time, the swing arm 825maintains the vertical state, and the scraping member 841 also maintainsthe vertical state, thereby collecting the sludge in the direction ofarrow X. Thus, the sludge is dropped into the pit 803.

In the scraping state, meanwhile, the swing arm 825 is vertical, and thewire 827 is set longer on the whole. At this time, the shortage oflength of the wire is absorbed as the lower sheave 837 ascends in thedrive source 832. When changing over from the scraping state to thereturn state, the operation is reverse, and the looseness is absorbed bythe drive source 832.

When the work member 815 is on the pit 803, the scraping state ischanged to the return state. The wire 827 is pulled in the direction ofarrow Y. As a result, the wire 827 is pulled through the fourth wheel831 and third wheel 830, and the swing arm 825 is tilted down from thevertical state through the second wheel 822. As a result, the work arm845 oscillates upward through the rotary shaft 817, and the work roller846 is raised to push up the oscillating arm 840. The scraping member841 is raised to be in return state. Afterwards, the work member 841begins to run, and returns to the left end in the diagram.

When the work member 815 comes to the left end and the wire 827 ispulled in the direction of arrow X, the swing arm 825 stands upvertically, and the work roller 846 is lowered, and the scraping arm 840is lowered by the return roller 847, so that the scraping member 841 isset in the specified scraping position by the stopper mechanism of thelower roller 842.

Besides, as shown in FIG. 30, in other constitution, a post 861 is setup on a work member 860, and a second wheel 862 is provided, and a wire865 from a first wheel 864 provided around the shaft of the travelingroller 863 is hooked on the second wheel 862, and by the action of thepulley, the scraping arm 866 is lifted thereby raising the scrapingmember. In the return state, the wire 865 is pulled through a thirdwheel 868 to pull down the scraping member 867.

INDUSTRIAL APPLICABILITY

Thus, the sludge scraping apparatus of the invention is very simple instructure of the apparatus and easy to install, while maintaining thescraping performance at high level, and hence it is suitable to anyapplication where low cost on the whole and low maintenance controlexpenses, or the like are required.

What is claimed is:
 1. A sludge scraping apparatus, for scraping sludgefrom a treatment pool, comprising:a monorail guide disposedlongitudinally in a sludge scraping direction of a treatment pool; awork member straddling said monorail guide and having a plurality ofrollers disposed in rolling contact with said monorail guide; a scrapingmember attached to said work member; and a scraping arm pivotallyattached to said work member and having said scraping member disposed onone end thereof; drive means for driving said work member in scrapingand non-scraping directions, said drive means being connected to anddriving said scraping arm to a non-scraping position when said workmember is driven in a non-scraping direction and to a scraping positionwhen said work member is driven in a scraping direction; wherein saiddrive means includes:an oscillating arm fixedly connected to saidscraping arm; at least one wire cable connected to said oscillating armto both pull said oscillating arm to a scraping or a non-scrapingposition and pulling said work member in a scraping or a non-scrapingdirection.
 2. The sludge scraping apparatus according to claim 1,wherein said plurality of rollers on said work member include at leastone pair of side rollers, one pair of upper rollers and one pair of holddown rollers.
 3. A sludge scraping apparatus, for scraping sludge from atreatment pool, comprising:a monorail guide disposed longitudinally in asludge scraping direction of a treatment pool; a work member straddlingsaid monorail guide and having a plurality of rollers disposed inrolling contact with said monorail guide; a pair of scraping membersattached to said work member; and a pair of scraping arms attached tosaid work member, said scraping members disposed on one end of arespective scraping arm; drive means for driving said work member inscraping and non-scraping directions, said drive means being connectedto and driving said scraping arms to a non-scraping position when saidwork member is driven in a non-scraping direction and to a scrapingposition when said work member is driven in a scraping direction;wherein said drive means includes:a pair of interlock arms connected tosaid pair of scraping arms; an interlock link connected between saidpair of interlock arms; a drive source; and wire cables connected toeach of said interlock arms and driven by said drive source to both pullsaid interlock arms to a scraping or a non-scraping position and pullingsaid work member in a scraping or a non-scraping direction.
 4. Thesludge scraping apparatus according to claim 3, wherein said pluralityof rollers on said work member include at least one pair of siderollers, one pair of upper rollers and one pair of hold down rollers. 5.A sludge scraping apparatus, for scraping sludge from a treatment pool,comprising:a monorail guide disposed longitudinally in a sludge scrapingdirection of a treatment pool; a work member straddling said monorailguide and having a plurality of rollers disposed in rolling contact withsaid monorail guide; a scraping member attached to said work member; anda scraping arm pivotally attached to said work member having saidscraping member disposed on one end thereof; drive means for drivingsaid work member in scraping and non-scraping directions, said drivemeans being connected to and driving said scraping arm to a non-scrapingposition when said work member is driven in a non-scraping direction andto a scraping position when said work member is driven in a scrapingdirection; wherein said drive means includes:a swing arm pivotallyconnected to said work member; a work roller connected to said swing armand in contact with said scraping arm such that when said swing arm isrotated in a first direction, said work roller moves said scraping armto a non-scraping position; a drive source; and wire cables connected tosaid swing arm and driven by said drive source to both pull said swingarm to a scraping or a non-scraping position and pulling said workmember in a scraping or a non-scraping direction.
 6. The sludge scrapingapparatus according to claim 5, wherein said plurality of rollers onsaid work member include at least one pair of side rollers, one pair ofupper rollers and one pair of hold down rollers.